Into the Torrid Zone
The lure of the tropics, the desire to visit a land of
relentless heat and humidity, of scorching sun and
torrential rain, may at first seem a bit hard to explain
(plate 1- 1). But it’s not. It can be explained in one
image: plate 1- 2.
Seeing a Jaguar (Panthera onca) for the first time, in
its element, its home, its piece of rain forest, is worth any
long bumpy and dusty ride, a few annoying mosquitos,
muddy boots, an airport delay, or any other minor
inconvenience typical of modern travel. Observing
a real live Jaguar in the wild provides a remarkable
connectivity with Earth’s natural world that is simply
unrivaled. You have really seen something special. And
there is so much more. The majesty of myriad imposing
tall rain forest trees and the chance of encountering
some of the multitudes of creatures that dwell within
those forests is an experience that is nothing short of
precious (plate 1- 3). The tropics, a land of heat and
humidity historically termed the Torrid Zone, contains
most of the world’s species of, well, pretty much
everything: plants, birds, mammals, reptiles, insects,
you name it. And that is what this book is about. We
are going to visit the Neotropics. Let’s begin with some
geographical perspective.
Beginning about 248 million years ago, just after
the end of the Permian period and the Paleozoic era,
the world’s continents began drifting apart, a process
that continues today. This separation is the result of a
dynamic geological process known as plate tectonics.
Continents made primarily of granite ride passively
atop large and slowly moving plates of basalt (which
compose the earth’s crust) kept in motion by the
convective heat of the planet itself. The result, in a
nutshell, has been that widely separated continents
now contain markedly different groups of organisms.
That is because 248 million years allow for a lot of
evolutionary change, for new species to diverge and
evolve, for whole new groups of organisms to develop.
For example, the primates of the New World tropics (the
Neotropics), the monkeys, marmosets, and tamarins
of Middle and South America, are distinctly different
from the Old World monkeys and apes, though they
all (along with us), of course, ultimately share common
ancestry in the order Primates (plate 1- 4).Chapter 1. Welcome to the Torrid Zone
Plate 1- 3. Tropical rain forest is the most structurally complex and biodiverse terrestrial ecosystem in the world.
Photo by John Kricher.
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